Preparation of Liposome Gel by Calcium Cross-Linking Induces the Long-Term Release of DOX to Improve the Antitumor Effect.

Doxorubicin (DOX) is one of the most commonly used anticancer drugs; however, its clinical application is greatly limited due to its toxicity and chemotherapy resistance. The delivery of DOX by liposomes (Lipos) can improve the blood circulation time in vivo and reduce toxic side effects, but the drug's accumulation in the tumor is often insufficient for effective treatment. In this study, we present a calcium cross-linked liposome gel for the encapsulation of DOX, demonstrating its superior long-term release capabilities compared to conventional Lipos. By leveraging this enhanced long-term release, we can enhance drug accumulation within tumors, ultimately leading to improved antitumor efficacy. Lipos were prepared using the thin-film dispersion method in this study. We utilized the ion-responsiveness of glutathione-gelatin (GSH-GG) to form the gel outside the Lipos and named the nanoparticles coated with GSH-GG on the outside of Lipos as Lipos@GSH-GG. The average size of Lipos@GSH-GG was around 342.9 nm, with a negative charge of -25.6 mV. The in vitro experiments revealed that Lipos@GSH-GG exhibited excellent biocompatibility and slower drug release compared to conventional Lipos. Further analysis of cellular uptake and cytotoxicity demonstrated that Lipos@GSH-GG loading DOX (DOX&Lipos@GSH-GG) exhibited superior long-term release effects and lower toxic side effects compared to Lipos loading DOX (DOX&Lipos). Additionally, the findings regarding the long-term release effect in vivo and the tumor accumulation within tumor-bearing mice of Lipos@GSH-GG suggested that, compared to Lipos, it demonstrated superior long-term release capabilities and achieved greater drug accumulation within tumors. In vivo antitumor efficacy experiments showed that DOX&Lipos@GSH-GG demonstrated superior antitumor efficacy to DOX&Lipos. Our study highlights Lipos@GSH-GG as a promising nanocarrier with the potential to enhance efficacy and safety by means of long-term release effects and may offer an alternative approach for effective antitumor therapy in the future.

Synthesis and Properties of Bright Red-to-NIR BODIPY Dyes for Targeting Fluorescence Imaging and Near-Infrared Photothermal Conversion.

An efficient synthesis of 3-pyrrolylBODIPY dyes has been developed from a rational mixture of various aromatic aldehydes and pyrrole in a straightforward condensation reaction, followed by in situ successively oxidative nucleophilic substitution using a one-pot strategy. These resultant 3-pyrrolylBODIPYs without blocking substituents not only exhibit the finely tunable photophysical properties induced by the flexible meso-aryl substituents but also serve as a valuable synthetic framework for further selective functionalization. As a proof of such potential, one 3-pyrrolylBODIPY dye (581/603 nm) through the installation of the morpholine group is applicable for lysosome-targeting imaging. Furthermore, an ethene-bridged 3,3'-dipyrrolylBODIPY dimer was constructed, which displayed a near-infrared (NIR) emission extended to 1200 nm with a large fluorescence brightness (2840 M-1 cm-1). The corresponding dimer nanoparticles (NPs) afforded a high photothermal conversion efficiency (PCE) value of 72.5%, eventually resulting in favorable photocytotoxicity (IC50 = 9.4 µM) and efficient in vitro eradication of HeLa cells under 808 nm laser irradiation, highlighting their potential application for photothermal therapy in the NIR window.

Bacterial outer membrane vesicle-cancer cell hybrid membrane-coated nanoparticles for sonodynamic therapy in the treatment of breast cancer bone metastasis.

Breast cancer bone metastasis is a terminal-stage disease and is typically treated with radiotherapy and chemotherapy, which causes severe side effects and limited effectiveness. To improve this, Sonodynamic therapy may be a more safe and effective approach in the future. Bacterial outer membrane vesicles (OMV) have excellent immune-regulating properties, including modulating macrophage polarization, promoting DC cell maturation, and enhancing anti-tumor effects. Combining OMV with Sonodynamic therapy can result in synergetic anti-tumor effects. Therefore, we constructed multifunctional nanoparticles for treating breast cancer bone metastasis. We fused breast cancer cell membranes and bacterial outer membrane vesicles to form a hybrid membrane (HM) and then encapsulated IR780-loaded PLGA with HM to produce the nanoparticles, IR780@PLGA@HM, which had tumor targeting, immune regulating, and Sonodynamic abilities. Experiments showed that the IR780@PLGA@HM nanoparticles had good biocompatibility, effectively targeted to 4T1 tumors, promoted macrophage type I polarization and DC cells activation, strengthened anti-tumor inflammatory factors expression, and presented the ability to effectively kill tumors both in vitro and in vivo, which showed a promising therapeutic effect on breast cancer bone metastasis. Therefore, the nanoparticles we constructed provided a new strategy for effectively treating breast cancer bone metastasis.

Hydrogels in Emerging Technologies for Type 1 Diabetes.

Type 1 diabetes therapies that afford tighter glycemic control in a more manageable and painless manner for patients has remained a central focus of next-generation diabetes therapies. In many of these emerging technologies, namely, self-regulated insulin delivery and cell replacement therapies, hydrogels are employed to mitigate some of the most long-standing challenges. In this Review, we summarize recent developments in the use of hydrogels for both insulin delivery and insulin-producing cell therapies for type 1 diabetes management. We first outline perspectives in glucose sensitive hydrogels for smart insulin delivery, pH sensitive polymeric hydrogels for oral insulin delivery, and other physiochemical signals used to trigger insulin release from hydrogels. We, then, investigate the use of hydrogels in the encapsulation of insulin secreting cells with a special emphasis on hydrogels designed to mitigate the foreign body response, provide a suitable extracellular microenvironment, and improve mass transfer through oxygen supplementation and vascularization. Evaluations of limitations and promising directions for future research are also considered. Continuing interdisciplinary and collaborative research efforts will be required to produce hydrogels with instructive biochemical microenvironments necessary to address the enduring challenges of emerging type 1 diabetes therapies.

Hydrolysis of propyrisulfuron in water: Kinetics, influence of 34 environmental factors, transformation products identification, mechanisms and toxicities.

Propyrisulfuron is a novel sulfonylurea herbicide used for controlling annual grass and broad-leaved weeds in fields, but its fates and behaviors in environment are still unknown, which are of utmost importance for environmental protection. To reduce its potential environmental risks in agricultural production, the hydrolysis kinetics, influence of 34 environmental factors including 12 microplastics (MPs), disposable face masks (DFMs) and its different parts, 6 fertilizers, 5 ions, 3 surfactants, a co-existed herbicide of florpyrauxifen-benzy, humic acid and biochar, and the effect of MPs and DFMs on its hydrolysis mechanisms were systematically investigated. The main hydrolysis products (HPs), possible mechanisms, toxicities and potential risks to aquatic organisms were studied. Propyrisulfuron hydrolysis was an acid catalytic pyrolysis, endothermic and spontaneous process driven by the reduction of activation enthalpy, and followed the first-order kinetics. All environmental factors can accelerate propyrisulfuron hydrolysis to varying degrees except humic acid, and different hydrolysis mechanisms occurred in the presence of MPs and DFMs. In addition, 10 possible HPs and 7 possible mechanisms were identified and proposed. ECOSAR prediction and ecotoxicity testing showed that acute toxicity of propyrisulfuron and its HPs for aquatic organisms were low, but may have high chronic toxicity and pose a potential threat to aquatic ecosystems. The investigations are significantly important for elucidating the environmental fates and behaviors of propyrisulfuron, assessing the risks in environmental protection, and further providing guidance for scientific application in agro-ecosystem.

Degradation of a New Herbicide Florpyrauxifen-Benzyl in Water: Kinetics, Various Influencing Factors and Its Reaction Mechanisms.

Florpyrauxifen-benzyl is a novel herbicide used to control weeds in paddy fields. To clarify and evaluate its hydrolytic behavior and safety in water environments, its hydrolytic characteristics were investigated under varying temperatures, pH values, initial mass concentrations and water types, as well as the effects of 40 environmental factors such as microplastics (MPs) and disposable face masks (DFMs). Meanwhile, hydrolytic products were identified by UPLC-QTOF-MS/MS, and its hydrolytic pathways were proposed. The effects of MPs and DFMs on hydrolytic products and pathways were also investigated. The results showed that hydrolysis of florpyrauxifen-benzyl was a spontaneous process driven by endothermic, base catalysis and activation entropy increase and conformed to the first-order kinetics. The temperature had an obvious effect on hydrolysis rate under alkaline condition, the hydrolysis reaction conformed to Arrhenius formula, and activation enthalpy, activation entropy, and Gibbs free energy were negatively correlated with temperature. Most of environmental factors promoted hydrolysis of florpyrauxifen-benzyl, especially the cetyltrimethyl ammonium bromide (CTAB). The hydrolysis mechanism was ester hydrolysis reaction with a main product of florpyrauxifen. The MPs and DFMs did not affect the hydrolytic mechanisms but the hydrolysis rate. The results are crucial for illustrating and assessing the environmental fate and risks of florpyrauxifen-benzyl.

Protection Effect of Curcumin for Macrophage-Involved Polyethylene Wear Particle-Induced Inflammatory Osteolysis by Increasing the Cholesterol Efflux.

BACKGROUND Periprosthetic osteolysis, induced by wear particles and inflammation, is a common reason for failure of primary arthroplasty. Curcumin, a nature phenol from plants, has been reported to reduce the inflammation in macrophages. This study aimed to investigate the potential effect of curcumin on macrophage involved, wear particle-induced osteolysis and its mechanism. MATERIAL AND METHODS RAW264.7 macrophages were used to test the effects of polyethylene (PE) particles and curcumin on macrophage cholesterol efflux and phenotypic changes. A mouse model of PE particle-induced calvarial osteolysis was established to test the effects of curcumin in vivo. After 14 days of treatment, the bone quality of the affected areas was analyzed by micro-computed tomography (micro-CT) and histology, and the bone surrounding soft tissues were analyzed at the cellular and molecular levels. RESULTS We found that PE particles can stimulate osteoclastogenesis and produce an M1-like phenotype in macrophages in vitro. Curcumin enhanced the cholesterol efflux in macrophages, and maintained the M0-like phenotype under the influence of PE particles in vitro. Additionally, the cholesterol transmembrane regulators ABCA1, ABCG1, and CAV1 were enhanced by curcumin in vivo. We also found enhanced bone density, reduced osteoclastogenesis, and fewer inflammatory responses in the curcumin treated groups in our mouse osteolysis model. CONCLUSIONS Our study findings indicated that curcumin can inhibit macrophage involved osteolysis and inflammation via promoting cholesterol efflux. Maintaining the cholesterol efflux might be a potential strategy to prevent periprosthetic osteolysis after total joint arthroplasty surgery.

Non-conjugated polymer carbon dots for fluorometric determination of metronidazole.

Non-conjugated polymer carbon dots (PCDs) with a 9% fluorescence quantum yield were synthesized by a pyrolytic method using polyethyleneimine as the sole precursor. The PCDs have an average size about 2.1 nm and a blue fluorescence, with excitation/emission maxima at 380/457 nm, that is quenched by the drug metronidazole. The method has a linear response in the 0.06-15 µg mL-1 metronidazole concentration range and a 20 ng mL-1 detection limit. Milk samples were spiked at two levels (0.6 and 5.0 µg mL-1), and the recoveries of metronidazole are in the range of 96.7-102.2%. Graphical abstract Schematic representation of preparation of non-conjugated polymer carbon dots (PCDs) and detection of metronidazole. Metronidazole with negative charge is easy to produce electrostatic interaction with polyethyleneimine chain with positive charge, which leads to PCDs fluorescence quenching, so as to realize metronidazole detection.

[Langerhans cell histiocytosis involving the oral and maxillofacial region: an analysis of 12 cases].

OBJECTIVE: To study the clinical features of Langerhans cell histiocytosis (LCH) involving the oral and maxillofacial region in children. METHODS: A retrospective analysis was performed for the clinical data of 12 children with LCH involving the oral and maxillofacial region who were hospitalized and treated from September 2012 to September 2017, including clinical manifestations, pathological features, treatment and prognosis. RESULTS: Of the 12 children, 8 (67%) had multiple system involvement and 7 (58%) had the involvement of organs at risk. Bone was the most common affected site (11 children, 92%), among whom 7 children had the involvement of the mandible. Oral soft tissue involvement manifested as gingival ulcer or hyperplasia in 4 children, loose teeth in 5 children, oral mucosal lesions in 2 children, and nodular lesions in 1 child. Pathological examination showed positive CDla in 11 children and positive CD207, CD68, S-100, and LCA in 12 children. Surgery combined with chemotherapy was the major treatment method, and surgical resection alone was performed for focal lesions. After treatment, 11 children were cured or improved and 1 gave up treatment and was lost to follow-up. No recurrence was observed. CONCLUSIONS: LCH children with oral and maxillofacial involvement often have the involvement of multiple systems and organs at risk, with the mandible as the most common affected site. These children may also have the involvement of gingiva, oral mucosa and teeth. Surgery combined with chemotherapy is the major treatment method, and the patients generally have a good prognosis without recurrence.

Curcumin Inhibits Polyethylene-Induced Osteolysis via Repressing NF-κB Signaling Pathway Activation.

BACKGROUND/AIMS: Aseptic loosening is a common reason for failed artificial hip replacement after total hip arthroplasty. Aseptic loosening is mostly the result of wear debris that causes osteolysis and weakens the structures that support the prosthesis. Wear debris plays a crucial role in osteolysis during the loosening process, and polyethylene (PE) particles are found as wear debris more frequently than any other type of particle. In the absence of effective therapeutic agents, osteolysis has been hard to treat. Previous studies have demonstrated that curcumin influences signalosome-associated kinases and the proteasome-ubiquitin system during osteoclastogenesis. The aims of this study were to explore the anti-osteolysis effect of curcumin and if possible to identify the signaling pathway involved in a model of PE-induced osteolysis. METHODS: Differentiation of osteoclasts was induced in vitro by PE particles in RAW264.7 (monocyte/macrophage) cells and in vivo by calvarial and air pouch models of osteolysis established by PE stimulation in mice. We performed a set of TRAP staining, realtime polymerase chain reaction (PCR), and Western blot experiments to evaluate the anti-osteolytic effect of curcumin by comparing specimens that were exposed and not exposed to curcumin. RESULTS: Curcumin had a promising inhibitory effect on osteolysis induced by wear debris and suppressed the RANK/c-Fos/NFATc1 signaling pathway. CONCLUSION: Curcumin can prevent PE-induced osteolysis and bone loss. An inhibitory effect on the RANK/c-Fos/NFATc1 signaling pathway may explain the anti-osteolysis activity of curcumin.

Transcription Factor NsdD Regulates the Expression of Genes Involved in Plant Biomass-Degrading Enzymes, Conidiation, and Pigment Biosynthesis in Penicillium oxalicum.

Soil fungi produce a wide range of chemical compounds and enzymes with potential for applications in medicine and biotechnology. Cellular processes in soil fungi are highly dependent on the regulation under environmentally induced stress, but most of the underlying mechanisms remain unclear. Previous work identified a key GATA-type transcription factor, Penicillium oxalicum NsdD (PoxNsdD; also called POX08415), that regulates the expression of cellulase and xylanase genes in P. oxalicum PoxNsdD shares 57 to 64% identity with the key activator NsdD, involved in asexual development in Aspergillus In the present study, the regulatory roles of PoxNsdD in P. oxalicum were further explored. Comparative transcriptomic profiling revealed that PoxNsdD regulates major genes involved in starch, cellulose, and hemicellulose degradation, as well as conidiation and pigment biosynthesis. Subsequent experiments confirmed that a ΔPoxNsdD strain lost 43.9 to 78.8% of starch-digesting enzyme activity when grown on soluble corn starch, and it produced 54.9 to 146.0% more conidia than the ΔPoxKu70 parental strain. During cultivation, ΔPoxNsdD cultures changed color, from pale orange to brick red, while the ΔPoxKu70 cultures remained bluish white. Real-time quantitative reverse transcription-PCR showed that PoxNsdD dynamically regulated the expression of a glucoamylase gene (POX01356/Amy15A), an α-amylase gene (POX09352/Amy13A), and a regulatory gene (POX03890/amyR), as well as a polyketide synthase gene (POX01430/alb1/wA) for yellow pigment biosynthesis and a conidiation-regulated gene (POX06534/brlA). Moreover, in vitro binding experiments showed that PoxNsdD bound the promoter regions of the above-described genes. This work provides novel insights into the regulatory mechanisms of fungal cellular processes and may assist in genetic engineering of Poxalicum for potential industrial and medical applications.IMPORTANCE Most filamentous fungi produce a vast number of extracellular enzymes that are used commercially for biorefineries of plant biomass to produce biofuels and value-added chemicals, which might promote the transition to a more environmentally friendly economy. The expression of these extracellular enzyme genes is tightly controlled at the transcriptional level, which limits their yields. Hitherto our understanding of the regulation of expression of plant biomass-degrading enzyme genes in filamentous fungi has been rather limited. In the present study, regulatory roles of a key regulator, PoxNsdD, were further explored in the soil fungus Penicillium oxalicum, contributing to the understanding of gene regulation in filamentous fungi and revealing the biotechnological potential of Poxalicum via genetic engineering.

Probing Membrane Fouling via Infrared Attenuated Total Reflection Mapping Coupled with Multivariate Curve Resolution.

Understanding membrane fouling induced by dissolved organic matter (DOM) is of primary importance for developing effective fouling control and prevention strategies. In this work, we combine multivariate curve resolution-alternating least squares analysis with infrared attenuated total reflection mapping to explore the fouling process of microfiltration and ultrafiltration membranes caused by two typical DOMs, humic acid (HA) and bovine serum albumin (BSA). The spectral contributions of different foulants and the membrane substrate were successfully discriminated, thereby enabling the diagnosis of fouling origins. Membrane fouling caused by HA is more severe than that by BSA. Three periods, the initial adsorption stage, the equilibrium stage, and the accumulation stage, were observed for the HA-induced fouling process. The integrated approach presented herein elegantly demonstrates the spatial and temporal characterization of membrane fouling processes, along with relative concentrations of the involved species, and suggests a promising perspective for understanding the interaction mechanisms between foulant species and membranes at the molecular level.

Cementless total hip arthroplasty in advanced tuberculosis of the hip.

PURPOSE: The use of total hip arthroplasty (THA) to treat advanced tuberculous arthritis, particularly during the active phase, is challenging. The aim of this study was to evaluate the efficacy of cementless THA for advanced hip joint tuberculosis. METHODS: This study reviewed 32 patients (mean age at surgery, 49.4 years [range, 24-79 years]) who underwent cementless THA between 2007 and 2012. All patients were diagnosed with advanced tuberculosis of the hip on the basis of clinical manifestations, radiographic findings, and histological examination. All procedures were performed by a single surgeon. Mean follow-up period was 4.1 years (range, 2-7 years). Thorough debridement of tuberculosis-infected tissues and antitubercular therapy were conducted intra-operatively. Clinical data, including visual analog scale (VAS) score, Harris hip score (HHS), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and complications, as well as radiologic data, including prosthesis subsidence and loosening, bone growth, and heterotopic ossification, were evaluated during follow-up. RESULT: Mean VAS decreased from 7.6 (range, 5-10) pre-operatively to 1.4 (range, 0-4) at final follow-up (P < 0.01). Mean HHS improved from 42.2 (range, 30-75) pre-operatively to 85.4 (range, 60-95) at final follow-up (P < 0.01). No signs of reactivation were detected. In all patients, ESR and CRP levels were within normal limits by a mean of three and four months, respectively, and radiologic results during follow-up indicated favourable prosthesis positioning and condition. CONCLUSION: Despite the state of tuberculosis, cementless THA was an effective treatment for advanced tuberculosis of the hip.

Identification of miRNAs involved in pear fruit development and quality.

BACKGROUND: MicroRNAs (miRNAs) are a class of small, endogenous RNAs that take part in regulating genes through mediating gene expressions at the post-transcriptional level in plants. Previous studies have reported miRNA identification in various plants ranging from model plants to perennial fruit trees. However, the role of miRNAs in pear (Pyrus bretschneideri) fruit development is not clear. Here, we investigated the miRNA profiles of pear fruits from different time stages during development with Illumina HiSeq 2000 platform and bioinformatics analysis. Quantitative real-time PCR was used to validate the expression levels of miRNAs. RESULTS: Both conserved and species-specific miRNAs in pear have been identified in this study. Total reads, ranging from 19,030,925 to 25,576,773, were obtained from six small RNA libraries constructed for different stages of fruit development after flowering. Comparative profiling showed that an average of 90 miRNAs was expressed with significant differences between various developmental stages. KEGG pathway analysis on 2,216 target genes of 188 known miRNAs and 1,127 target genes of 184 novel miRNAs showed that miRNAs are widely involved in the regulation of fruit development. Among these, a total of eleven miRNAs putatively participate in the pathway of lignin biosynthesis, nine miRNAs were identified to take part in sugar and acid metabolism, and MiR160 was identified to regulate auxin response factor. CONCLUSION: Comparative analysis of miRNAomes during pear fruit development is presented, and miRNAs were proved to be widely involved in the regulation of fruit development and formation of fruit quality, for example through lignin synthesis, sugar and acid metabolism, and hormone signaling. Combined with computational analysis and experimental confirmation, the research contributes valuable information for further functional research of microRNA in fruit development for pear and other species.

Bioreducible nanocapsules prepared from the self-assembly of branched polymer in nanodroplet.

Though great attention has been paid in constructing well-defined nano-structures via the self-assembly of amphiphilic macromolecules, the self-assembly of non-amphiphilic macromolecules in nanodroplet has drawn less attention up to now. Recently, we prepared a temperature-responsive PEG-based branched polymer with disulfide bonds in its backbone via reversible addition-fragmentation chain transfer (RAFT) polymerization of 2-(2-methoxyethoxy) ethyl methacrylate, oligo(ethylene glycol) methacrylate, and N,N'-cystamine bisacrylamide. Subsequently, we loaded the branched polymer into nanodroplets, and have found that the self-assembly behaviors of this branched poly-mer in the nanodroplet are different from those in common solution. Bioreducible nanocapsules with tunable size can easily formed in nanodroplet even at high concentration.

Experimental Study on the Migration and Distribution of Microplastics in Desert Farmland Soil Under Drip Irrigation.

The microplastics (MPs) formed by broken plastic film may migrate in the soil under drip irrigation. To investigate the migration distribution of MPs in desert farmland soil under drip irrigation conditions, our study was conducted on farmland in Xinjiang (China). A MP drip irrigation penetration migration testing device was set up in combination with Xinjiang farmland irrigation methods to conduct a migration simulation experiment. The results showed that the migration amount of MPs in soil was significantly positively correlated with the amount of drip irrigation, and significantly negatively correlated with the soil depth; in addition, the relationship between the migration amount of MPs in different types of soil was: clay < sandy loam < sandy soil. Under drip irrigation conditions, the migration rates of MPs were 30.51%, 19.41%, and 10.29% in sandy soil, sandy loam soil, and clay, respectively. The migration ability of these three particle sizes of polyethylene MPs in soil was ranked as follows: 25 to 147 µm > 0 to 25 µm > 147 to 250 µm. When the drip irrigation volume was 2.6 to 3.2 L, horizontal migration distances of MPs exceeded 5 cm, and vertical migration distances reached more than 30 cm. Our findings provide reference data for the study of soil MP migration. Environ Toxicol Chem 2024;43:1250-1259. © 2024 SETAC.

Supercritical CO2 extrusion foaming of highly open-cell poly(lactic acid) foam with superior oil adsorption performance.

Addressing marine oil spills and industrial water pollution necessitates the development of eco-efficient oil-absorbing materials. With increasing concern for the environment, there is a consensus to decrease the use of petroleum-based polymers. Herein, lightweight poly(lactic acid) (PLA) blend foams with varying thermoplastic polyurethane (TPU) content were fabricated via a solvent-free, eco-friendly supercritical carbon dioxide (scCO2) extrusion foaming technology. The incorporation of TPU significantly enhanced the crystallization rate of PLA, with the semi-crystallization time of PT30 and PT50 blends at 105 °C exhibiting a reduction of 77.2 % and 47.9 %, respectively, compared to neat PLA. The resulting foams exhibited an open-cell structure with excellent selective oil adsorption capabilities. Notably, the PT30 foam achieved a remarkable maximum expansion ratio of 36.0, while the PT50 foam attained the highest open-cell content of 96.2 %. The PT50 foam demonstrated an outstanding adsorption capacity, spanning from 4.7 to 18.8 g/g for diverse oils and solvents, with rapid adsorption kinetics, reaching 94.9 % of the equilibrium adsorption capacity for CCl4 within just 1 min. Furthermore, the PT50 foam retained 95.2 % of its adsorption capacity for CCl4 over 10 adsorption-desorption cycles. This study presents a scalable and sustainable approach for large-scale production of high-performance, bio-based foams, facilitating efficient oil-water separation.

Distribution Characteristics of Atmospheric Microplastics in Typical Desert Agricultural Regions.

We examined the distribution characteristics of atmospheric microplastics in typical desert agricultural regions, with a focus on the agricultural areas surrounding the Taklamakan Desert, Xinjiang, China. We collected samples of total suspended particulate matter (TSP), atmospheric deposition, and atmospheric dust using both active and passive collection methods. The chemical composition, particle size, shape, and color of atmospheric microplastics were examined using a stereomicroscope and a Fourier-transform infrared spectrometer to analyze their characteristics. The results showed that the primary chemical compositions of microplastics included polypropylene (PP), polyethylene, polyethylene terephthalate, polymethylmethacrylate, and cellophane. Particle sizes were mainly within the range of 0 to 1000 µm. Fibrous microplastics constituted the majority of the TSP and atmospheric deposition, whereas film-like microplastics constituted the largest proportion of atmospheric dustfall. The deposition flux of atmospheric microplastics in the first quarter was measured at 103.21 ± 22.12 particles/m2/day, which was lower than that observed in conventional agricultural areas. The abundance of microplastics in atmospheric dustfall was found to be 1.36 particles/g. The proportion of PP microplastics in atmospheric dustfall can be as high as 35%. Through a comparison of microplastic content in TSP during dust storms and under normal weather conditions, it was found that dust storms can lead to an increase in the abundance of microplastics within the atmospheric TSP. The present study provides a scientific basis for understanding the distribution of atmospheric microplastics in typical desert agricultural regions. Environ Toxicol Chem 2024;43:1982-1995. © 2024 SETAC.

A novel twisted rotor blade suitable for high-speed turbomolecular pumps: Numerical modelling and structural optimisation.

To meet the urgent need for a new design concept and solve the inaccuracy of existing performance prediction algorithms for high-speed turbomolecular pumps (TMPs), a new algorithm based on a novel twisted rotor blade is proposed. In this algorithm, the blade angle of the turbine rotor row progressively decreases from the root to the tip of the blade tooth. The feasibility and accuracy of the simulation algorithm were verified through experiments. The dependence of the simulation results on the number of simulated molecules was discussed. Both theoretical analysis and simulations confirmed the necessity of setting a twisted rotor blade in the turbine combined blade row. A comparative analysis on the performance of conventional straight-blade and twisted-blade structures based on the first-four stages of turbine combined blade rows of the F-63/55 TMP was conducted. The results indicated that the maximum pumping speed coefficient and maximum compression ratio of the optimised twisted-blade structure increased by 4.59% and 22.26%, respectively. This novel blade structure overcomes the limitations of the conventional straight-blade structure. Progressively decreasing the rotor blade angle from the root to the tip of the blade tooth is beneficial for improving the performance of TMPs. This study provides a new design concept and performance prediction algorithm for the structural optimisation of high-speed TMPs.

Biodegradable nanofibrillated microcellular PBS/PLA foams for selective oil absorption.

To address the challenges posed by spilled oil and oily wastewater, the development of clean oil-adsorption materials is crucial. However, traditional oil-adsorption materials suffer from the issue of secondary pollution. Herein, fully biodegradable nanofibrillated poly(butylene succinate)/poly(lactic acid) (PBS/PLA) foams with outstanding selective oil-adsorption performance were successfully fabricated via an eco-friendly supercritical CO2 foaming technology. The PBS/PLA composites, featuring nanofibrils with a diameter of approximately 100 nm, were prepared through a hot-stretching method subsequent to extrusion. Substantial improvements were observed in the crystallization rate and rheological properties of the fibrillated PBS/PLA composites. Furthermore, PLA nanofibrils enhanced foamability of the composite, achieving an impressive expansion ratio of up to 38.0, resulting in an outstanding oil-absorption performance (19.2-50.4 g/g) of the F-1 %-95 foam. Additionally, 20 adsorption-desorption cycles illustrated the prepared F-1 %-95 foam displayed recyclable oil-absorption characteristics. This work provides an eco-friendly strategy for preparing fully biodegradable foams intended for application as oil-adsorption materials.